The document discusses various methods to mitigate floods, including building structures like levees and floodwalls to increase a river's carrying capacity, improving river channels, and changing how humans interact with nature through regulations and disaster preparedness. Levees raise river banks while floodwalls are structures built along river banks or floodplains. Channel improvements involve dredging rivers to make them deeper and wider to allow water to flow faster. Zoning laws decide which areas are used for activities, reserving flood-prone areas for parks. Elevating properties requires buildings in flood areas to be above a certain height.

1. managing floods

2. why are some places
more affected
by the impacts of floods
than others?

3. why are some places
more affected
by the impacts of floods
than others?
because some places did more
to mitigate floods than others

4. why are some places
more affected
by the impacts of floods
than others?
because some places did more
to mitigate floods than others
= reduce impact of a phenomenon

5. lesson objectives

6. lesson objectives
describe various methods to mitigate floods

7. lesson objectives
describe various methods to mitigate floods
explain how it brings about advantages

8. lesson objectives
describe various methods to mitigate floods
explain how it brings about advantages
explain how it brings about challenges

9. ways to mitigate floods

10. ways to mitigate floods
(i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods

11. ways to mitigate floods
(i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem

12. ways to mitigate floods
(i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem
(a)invest in infrastructure
- levees and floodwalls
- channel improvements

13. ways to mitigate floods
(i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem
(a)invest in infrastructure
- levees and floodwalls
- channel improvements
(a)Regulation
- Zoning
- Elevated Properties
(b)Disaster preparedness
- Forecast and warning
systems
- Evacuation Drills

14. (i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(a)invest in infrastructure
- levees and floodwalls
- channel improvements
ways to
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem
(a)Regulation
- Zoning
- Elevated Properties
(b)Disaster preparedness
- Forecast and warning
systems
- Evacuation Drills

15. Levees
= raised river banks
(side of river)
Floodwalls
= structures to hold
more water

16. River
River
Banks
Floodplains Floodplains
River
Banks

17. River
Levees
- Raised sides
River
Banks
Floodplains Floodplains
River
Banks

18. Flood walls
- structures built
River
Levees
- Raised sides
River
Banks
Floodplains Floodplains
River
Banks

19. River
River
Banks
Floodplains Floodplains
River
Banks

20. River
Levees
-only at river banks
River
Banks
Floodplains Floodplains
River
Banks

21. River
Levees
-only at river banks
Flood walls can be built anywhere
on floodplains too
River
Banks
Floodplains Floodplains
River
Banks

22. Explain how levees & floodwalls
prevent floods
Levees
& Floodwalls
Prevent floods

23. Levees
& Floodwalls
Prevent floods
- water exceeds
carrying capacity
- overflows into
usually dry areas
Explain how levees & floodwalls
prevent floods

24. Levees
& Floodwalls
Prevent floods
- prevents water
from exceeding its
carrying capacity
- prevents it from
overflowing into
usually dry areas
Explain how levees & floodwalls
prevent floods

25. Levees
& Floodwalls
Prevent floods
- prevents water
from exceeding its
carrying capacity
- prevents it from
overflowing into
usually dry areas
- Levees =
raised river
banks
- Floodwalls =
structures
built on river
banks /
floodplains
Explain how levees & floodwalls
prevent floods

26. Levees
& Floodwalls
Prevent floods
- prevents water
from exceeding its
carrying capacity
- prevents it from
overflowing into
usually dry areas
- Levees =
raised river
banks
- Floodwalls =
structures
built on river
banks /
floodplains
What did it do?
increases
carrying capacity,
so that it
Explain how levees & floodwalls
prevent floods

27. levees & floodwalls
cheaper
benefits

28. levees & floodwalls
cheaper
than raising
the height of
surrounding land
raised land
benefits

29. levees & floodwalls
cheaper
than raising
the height of
surrounding land
benefits challenges
regular maintenance required
= strong enough to hold back floods

30. This is what
happens
when it is
not maintained
regularly
=
collapse and
cannot hold
water anymore

31. levees & floodwalls
cheaper
than raising
the height of
surrounding land
benefits challenges
regular maintenance required
= strong enough to hold back floods
designed to hold back floodwaters
up to a certain height only.
Unable to prevent floods beyond
that level

32. What happens if the water is higher
than the design of the floodwalls?
=
Flood still happens

33. (i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(a)invest in infrastructure
- levees and floodwalls
- channel improvements
ways to
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem
(a)Regulation
- Zoning
- Elevated Properties
(b)Disaster preparedness
- Forecast and warning
systems
- Evacuation Drills

34. channel improvement
After Channel Improvement
River Channel
Dredged to be
Deeper and Wider
Previous Channel
Shape
Before Channel Improvement
Rough
River channel Obstacles
(Rocks, Boulders)
= increase carrying capacity
= make river / channel flow faster
1) By making river/canal deeper and wider

35. channel improvement
After Channel Improvement
River Channel
Dredged to be
Deeper and Wider
Previous Channel
Shape
Before Channel Improvement
Rough
River channel Obstacles
(Rocks, Boulders)
= increase carrying capacity
= make river / channel flow faster
2) By making river/canal flow faster

36. Explain how channel
improvements prevent floods
Channel
Improvements
Prevent floods

37. Prevent floods
- water exceeds
carrying capacity
- overflows into
usually dry areas
Explain how channel
improvements prevent floods
Channel
Improvements

38. Prevent floods
- prevents water
from exceeding its
carrying capacity
- prevents it from
overflowing into
usually dry areas
Explain how channel
improvements prevent floods
Channel
Improvements

39. Prevent floods
- prevents water
from exceeding its
carrying capacity
- prevents it from
overflowing into
usually dry areas
- river channel
or canal is
made
deeper and
wider
- make river
flow /
channel flow
faster
Explain how channel
improvements prevent floods
Channel
Improvements

40. Prevent floods
- prevents water
from exceeding its
carrying capacity
- prevents it from
overflowing into
usually dry areas
What did it do?
increases
carrying capacity,
so that it
- river channel
or canal is
made
deeper and
wider
- make river
flow /
channel flow
faster
Explain how channel
improvements prevent floods
Channel
Improvements

41. Channel Improvements
possible for
moderate-value
and high-value
development
to take place at land
next to river
channels and
canals
benefits
moderate / high value
development = building things
that can earn a lot of money. Eg:
Offices, condominiums
Using Channel Improvement
Using other methods
(Eg: leeves and flood walls)
Land can’t be used for
development to hold floods

42. Channel Improvements
possible for
moderate-value
and high-value
development
to take place at land
next to river
channels and
canals
benefits
moderate / high value
development = building things
that can earn a lot of money. Eg:
Offices, condominiums
challenges
May create problems for areas
upstream or downstream of the
improved area
upstream = areas closer to start
of channel
downstream = areas closer to
end of river

44. Direction
of channel
flow

45. Part of channel
we are looking at
Direction
of channel
flow

46. Part of channel
we are looking at
Direction
of channel
flow
Upstream

47. Part of channel
we are looking at
Direction
of channel
flow
Upstream
downstream

48. Part of channel
we are looking at
Direction
of channel
flow
Upstream
downstream
If water flows
too fast here
due to channel
improvement

49. Part of channel
we are looking at
Direction
of channel
flow
Upstream
downstream
If water flows
too fast here
due to channel
improvement
too little water left
= insufficient for animals living there

50. Part of channel
we are looking at
Direction
of channel
flow
Upstream
downstream
If water flows
too fast here
due to channel
improvement
too little water left
= insufficient for animals living there
too much water flow into here
= flood easily

51. (i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(a)invest in infrastructure
- levees and floodwalls
- channel improvements
ways to
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem
(a)Regulation
- Zoning
- Elevated Properties
(b)Disaster preparedness
- Forecast and warning
systems
- Evacuation Drills

52. (i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(a)invest in infrastructure
- levees and floodwalls
- channel improvements
ways to
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem
(a)Regulation
- Zoning
- Elevated Properties
(b)Disaster preparedness
- Forecast and warning
systems
- Evacuation Drills
DO
NE

53. (i) Build structures to
increase
carrying capacity
= less likely to exceed
carrying capacity and cause
floods
(a)invest in infrastructure
- levees and floodwalls
- channel improvements
ways to mitigate floods
(ii) Change how
humans interact with
nature
= let flood occur, but find ways
to lessen it from being a
problem
(a)Regulation
- Zoning
- Elevated Properties
(b)Disaster preparedness
- Forecast and warning
systems
- Evacuation Drills
DO
NE

54. regulation

55. regulation = law

56. regulation = law
1) Zoning
= law by government that decides
which places should be used for
industrial, commercial or recreational activities

57. regulation = law
1) Zoning
= law by government that decides
which places should be used for
industrial, commercial or recreational activities
high value <-
as they bring in a
lot of money low value <-
as they don’t
bring in much
money

58. regulation = law
1) Zoning
flood prone areas - zoned for low value development
further from flood-prone areas - zone for higher value
development
Flood prone - reserved for parks
Less prone to floods = used for
high-value development
Less prone to floods = used for
high-value development

59. regulation = law
2) Elevated properties
= law that says buildings at a particular area must
be be built above a certain height

60. Why climb up the stairs just to go down again?

61. Why climb up the stairs just to go down again?
MPL

62. Why climb up the stairs just to go down again?
MPL
so if floods
come…

63. Why climb up the stairs just to go down again?
MPL
so if floods
come…

64. Why climb up the stairs just to go down again?
MPL
so if floods
come…
MRT stations
are
protected
from floods
= less impact

65. practice the mission
on coursemology!